Lamp sealing apparatus



y 1958 R. G. CALDWELL 2,844,917

LAMP SEALING APPARATUS Filed Oct. 21, 1953 5 Sheets- Sheet 1 Inventor: Q A Richard G. Caldwell,

W W His Attorney July 29, 1958 R. G. CALDWELL LAMP SEALING APPARATUS 3 Sheets-Sheet 2 Filed Oct. 21, 1953 4 --To PU His Attorney 29, 1958 v R. G. CALDWELL 2,844,917

- LAMP SEALING APPARATUS Filed Oct. 21, 1953 3.Sheets-Sheet 5- Inventor; Richard G. Caldwell, byM

His Attorney United States Patent LAMP SEALING APPARATUS Richard Gladen Caldwell, Flora, Miss., assignor to General Electric Company, a corporation of New York Application ()ctoher 21, 1953, Serial No. 387,494

Claims. (Cl. 49-2) My invention relates in general to the manufacture of electric lamps of the double-ended type having a mount sealed into each end thereof, and more particularly to apparatus for sealing the mounts into the opposite ends of the tubular envelope of the lamp.

In the manufacture of tubular fluorescent lamps of the type in general use at present, a separate lamp mount or stem assembly, comprisiing a glass stem having lead-in wires sealed therethrough and supporting an electrode thereon, is sealed into each end of the tubular glass lamp envelope. The sealing operation is generally carried out on a sealing machine customarily comprising a horizontal turret which supports and holds the tubular lamp envelope in a vertical position with its lower end resting on the glass stem portion of the lamp mount, and then indexes the so-positioned envelope and mount through a series of sealing stations where they are suitably heated, as by gas fires, to fuse and seal the envelope end to the glass stem of the mount.

After the sealing of one end of the lamp, the customary practice heretofore has been to manually remove the lamp from the sealing turret, turn it end for end, and

then place it back on the sealing turret with its lower unsealed end in sealing relation to another lamp mount placed on the turret. Such a manual lamp inverting operation, however, besides requiring the added services of an operator, is very inconvenient to perform where the lamp is of appreciable length, such as in the ase of the conventional four foot long fluorescent lamps in common use at present. Because of their considerable length, such lamps are unwieldy and awkward to handle. For such reason, it is difficult to prevent the lamps from striking against objects in the immediate vicinity (such as the sealing machine or other adjacent apparatus) and becoming broken during the inverting operation. Also, there is the likelihood of the lamp striking persons located in the immediate vicinity and not only becoming broken but also causing injury to such persons.

It is an object of my invention, therefore, to provide a sealing apparatus for tubular type lamps which will operate to automatically seal one end of a tubular lamp envelope and then invert the lamp and seal the other end thereof.

Another object of my invention is to provide a mechanism positive in operation for automatically inverting tubular lamp envelopes on lamp manufacturing machines of the type comprising an indexing carrier with a plurality of envelope carrying heads mounted on the pe- 2,844,917 Patented July 29, 1958 A further object of my invention is to provide a double-turret type automatic sealing machine for sealing the lower ends of tubular lamp envelopes positioned on each sealing turret, together with a combination transfer and inverting mechanism for automatically transferring the lamp envelopes from one turret to the other, and positioning them in inverted position on the second turret.

In accordance with one aspect of my invention, two conventional turret-type lamp'sealing machines are positioned in adjacent side-by-side relation with a common drive means for indexing them in timed relation with each other, and a horizontal transfer arm provided with lamp gripping means and operating in timed relation to the index movements of the sealing turrets is mounted in a position between the two sealing turrets and is arranged to grip the lamp at the unloading station of one of said turrets and then swing in a horizontal plane and rotate about a horizontal axis to simultaneously transfer and invert the lamp and place it in a lamp holder of the second turret at the loading station thereof.

Further objects and advantages of my invention will appear from the following detailed description of a species thereof and from the accompanying drawings.

In the drawings:

Fig. 1 is a plan view of sealing apparatus comprising my invention;

Fig. 2 is a fragmentary perspective view of the lamp transfer and inverting mechanism of the sealing apparatus in position for transferring a lamp envelope from one of the heads of the first sealing turret to the second sealing turret, along with a diagrammatic illustration of a control valve for an actuating hydraulic or oil cylinder;

Fig. 3 is a vertical section through the lamp transfer and inverting mechanism; 7

Fig. 4 is a vertical section, on an enlarged scale, taken on the line 44 of Fig. 3; and

Fig. 5 is a fragmentary section, on an enlarged scale, of the thrust coupling portion of the lamp transfer and inverting mechanism.

The invention is herein shown and described as applied to apparatus for sealing the stern assemblies or lamp mounts of a tubular discharge lamp 1 to the opposite'ends of the lamp envelope 2. As shown in Fig. l, the apparatus comprises a pair of conventional type fluorescent lamp sealing machines 3 and 4 mounted in adjacent side-by-side relation on a common base or frame 5 and operating in timed relation to each other. The sealing machines 3, 4 may be of the general type described and claimed in U. s. Patent No. 2,434,664, F. J. Malloy, dated January 20, 1948, employing gas fires to fuse and seal the glass stem assemblies to the ends of the glass lamp envelope, the machineseach comprising respective horizontal turrets or carriers 6 and 6' provided with a plurality (16) of heads 7 and '7, respectively, located at uniformly spaced intervals around the peripheral region of the respective turret. The turrets 6, 6 are supported on vertical shafts 8, 8', respectively, journaled in the machine frame 5, and they are intermittently rotated in a counterclockwise direction in timed relation to each other to successively index or advance the respective heads 7, 7' to a plurality of work stations A to Q and A to Q, respectively, corresponding in number to the number of heads on each turret. The indexing means for the turrets 6, 6' may be of any well-known type, for instance, such as that illustrated in U. S. Patent No. 1,742,153, Stiles et al., and comprising a rotating drum-type cam 9, 9' for the respective turret mounted on a. common drive or cam shaft 10 and engaging with a plurality of rollers 11, 11, respectively, depending from discs 12 and 12' fastened to the respective turret support shafts 8, 8. It will be appreciated that the invention requires only that the turrets be driven in unison, that is, station for station; obviously, this could be achieved by separate synchronous or synchronously regulated motor drives as well as by a single common drive.

The heads 7 and 7 on the respective turrets 6 and 6 each comprise a vertically extending spindle 13 journaled in the turret and arranged to support on its upper end a conventional type lamp mount in proper sealing position relative to the lower end of a tubular lamp envelope 2 held in a vertical position in .a holder 14 carried by the spindle 13. The holder 14, which may be of the general type disclosed in U. S. Patent No. 2,512,277, H. W. Iacobsen, comprises opposed pivoted jaws 15, 16 which are pivotally mounted on a bracket 13 carried by the spindle 13 and are normally held in closed position, to grip the lamp envelope 2 therebetween, by means of a coil spring 17 anchored at one end to the bracket portion 13' of the holder 14 and connected at its other end to an operating lever 18 for pivoting the jaws 15, 16. The holder 14 is also provided with vertically spaced guides or back stops 19 for the envelope having V- shaped envelope-receiving recesses 20 which, when the holder is in its loading and unloading positions at stations A, B and Q (or A, B' and P, Q), respectively, face radially outward of the turret, as shown in Fig. 1.

In the operation of each sealing machine, the lamp mount and envelope are placed in sealing relation on the spindle 13 and in the holder 14, respectively, of the head 7 or 7 at the loading stations A, B and A, B of the respective sealing machine, after which the turret 6 or 6 indexes the head successively through the work stations C to P and C to O', at some of which the glass.

envelope and glass flare of the mount are heated by gas fires from burners (not shown) located thereat to effect the fusion and sealing together of the glass parts, and thence to the unloading stations Q and P, Q where the sealed envelope and mount are removed from the heads 7 or 7'. One end of the lamp envelope 2 is sealed in the first sealing machine 3 after which the envelope is transferred to and mounted in an inverted position inthe' second sealing machine 4 and the other end of the envelope then sealed.

In accordance with the invention, the transfer and inversion of the lamp envelope 2 from the first sealing machine 3 to the second machine 4 is performed automatically by a transfer mechanism T operating in timed relation to the index movements and dwell intervals of the two sealing turrets 6, 6'. To enable such transfer operation, suitable means are provided for first lifting the envelopes 2 on the first turret 6 off the upper ends of their respective spindles 13, at one of. the stations preceding the unloading station Q (preferably at the immediately preceding station P as shown), in order to withdraw the customary exhaust tubes depending from the lower ends of the envelopes from the passageways provided therefor in the spindles so as to clear the upper ends of the spindles and permit lateral transfer movement of the envelopes from the heads 7 without breakage of the exhaust tubes. The particular envelope lift-up means shown comprises a head assembly 120 having a pair of envelope gripping jaws 21, 22 (Fig. 1) pivotally mounted on a bracket 23 to swing in' a horizontal plane and provided with sector gear portions which are meshed with and rotated by a horizontally reciprocable rack gear 24 to open and close the jaws. The rack gear 24 is connected to and actuated by the piston of a two-way hydraulic or oil cylinder 25 fastened to the bracket 23. The supply of oil under pressure to the cylinder 25, and thus the opening and closing of'the jaws 21, 22, is regulated in timed relation tothe dwell of the turret 6 by suitable means, as by a four-way hydraulic valve connected in the oil supply line for the cylinder and operated from the camshaft 10. A similar valve is described hereinafter in connection with cylinder 65 on transfer mechanism T and is illustrated in Fig. 2.

The entire head assembly is pivotally mounted on a horizontal support arm 26 for limited horizont'al'swing' movement to permit self adjustment of the jaws 21, 22 and the entire head assembly 120 into alignment with the lamp envelope 2 when the jaws are closed thereagainst. The support arm 26 is fastened to and moved up and down by a vertically extending lift rod 27 vertically reciprocable in a bearing 28 fixedly mounted on a stationary portion of the machine frame. The lift rod 27 is raised and lowered by an operating lever arm 29 which is pivotally mounted intermediate its ends on a support bracket 30 fastened to a stationary part of the machine frame and is connected at one end to the lift rod' 27 and is provided at its other end with a roller 31 which rides in the cam slot of a face cam 32 mounted on the cam shaft 10.

The four-way hydraulic valve controlling the supply of oil under pressure to the cylinder 25, and the cam 32 controlling the up and down movement of the entire envelope lift head assembly 120, are so arranged as to hold the latter in its lowered position during the index of the turret 6' and at the same time hold the envelope gripping jaws 21, 22 in their open or envelope disengaged position in which they extend oppositely away from each other so as to be clear of the envelopes 2 in the heads 7 and permit their index movement to and away from station P without interference therewith. During each dwell interval of the turret, the hydraulic cylinder 25 is actuated to close the jaws 21, 22 against the envelope 2 in the head 7 at station P, whereupon the entire envelope lift head assembly 120 is raised to its up position to lift the envelope 2 and withdraw the exhaust tube thereof from the associated head spindle 13, the grip of the envelope holder jaws 15, 16 of the head 7 against the envelopes 2 being sufficiently light to permit vertical sliding movement of the envelopes through the said jaws 15, 16 by the envelope lift-up jaws 21, 22. Upon completion of the envelope lift-up movement, the lift jaws 21, 22 are then swung open by the operation of the cylinder 25 and rack gear 24 so as to clear the envelope 2 and permit its subsequent index to the next station, following which the entire envelope lift head assembly 120 is lowered to its down position in readiness for its next envelope lift-up cycle.

Upon index of the elevated envelope 2 to the unloading station Q, it is picked up by the transfer mechanism T and then simultaneously turned end for end and transferred into the head 7' at the loading station B of the second sealing turret 6'. The transfer mechanism T for accomplishing this operation comprises a horizontally extending transfer arm 33 located between the two turrets 6 and 6 and comprising a hollow shaft rotatably supported in bearings 34 fastened on a housing 35 which is mounted on the upper end of a vertically extending hollow support shaft 36. The shaft 36 is rotatably supported. in spaced bearings 37 mounted on an upstanding openwork support column or standard 38 which is fastened at its lower end on a stationary table portion 39 of the machine framework. The transfer arm 33 is oscillated in a horizontal plane between its lamp pick-up position as shown in solid lines in Fig. 1 wherein it grips a lamp 1 in the head 7 at station Q, and a delivery position as shown in dotted lines in Fig. 1 wherein it places the said lamp in inverted position in the head 7' at station B of the second turret 6'. The swinging movement or oscillation of the transfer arm 33 is effected by a more or less vertically extending lever arm 40 which is pivoted at its lower end on a stationary bracket 41 mounted on the base or bed 5 of the machine and is pivotally connected at its upper end to one end of a connecting rod or link 42 the other end of which is pivotally connected to a crank arm 43 fastened to the lower end of the vertical support shaft 36. The lever arm 40 carries a roller 44 at a point intermediate its pivotal connections to the bracket 41 and connecting rod 42, which roller 44 rides in the cam groove of a face cam 45 mounted on the cam' shaft 10.

Adjacent its outer or free end, the transfer arm 33 carries an envelope holder 46 comprising a support bracket 47 (Fig. 2) fixedly secured to the transfer arm 33 and on which a pair of parallel side-by-side shafts 48 and 49 are rotatably mounted to extend at approximately right angles to the axis of the transfer arm 33 and in a vertical direction when the transfer arm is in either its envelope pick-up or delivery position. Shaft 48 carries a pair of envelope-engaging jaws 50, 50 fixedly secured to the shaft at spaced points therealong, while shaft 49 carries a cooperating opposed jaw 51 fixedly secured thereto at a point intermediate the two jaws 50, 50. The lamp envelopes 2 are gripped and held in a fixed position between the jaws 50 and 51 of the holder 46 during the lamp transfer operation, the jaws for such purpose being provided with V-shaped envelope-receiving notches 52 which hold the lamp envelopes in fixedposition in the jaws and which not only align with the envelopes 2 in the head 7 at station Q of the first turret 6' when the transfer arm is in its envelope pick-up position but which also position the transferred envelope 2 in vertical alignment with the head 7 at the envelope loading station B of the second turret 6 when the transfer arm is swung to its envelope delivery position.

The jaws 50, 51 are swung into their open or closed positions by an actuating rod 53 which extends through the bore of the hollow transfer arm 33 and is pivotally connected by a pin and slot connection to a yoked swing lever 54 which extends through an opening 55 in the bracket 47 and is fixedly secured to jaw shaft 48. The jaw shaft 48 transmits its rotational movement, in reverse, to the other jaw shaft 49 by means of intermeshed spur gears 56, 57 mounted on the shafts 48 and 49, respectively. The pin and slot connection between the actuating rod 53 and swing lever 54 is formed by oppositely extending pins 58 on a saddle block 59 carried by the actuating rod 53 and slidable within a longitudinally extending slot 60 in the transfer arm 33, the pins 58 extending into and riding in slots 61 in the two arms 62, 62 of the swing lever 54. The actuating rod 53 extends from the holder 46 through the transfer arm 33 and its support housing 35 to the opposite side thereof where it is connected, through a two-way thrust bearing 63, to the piston rod 64 of a double-acting oil cylinder 65 fixedly secured to the outer end of a support tube 66 fastened at its other or inner end to the support housing 35. Operation of the hydraulic cylinder 65 reciprocates the actuating rod 53, causing it to swing the lever 54 and pivot the jaws 50, 51 of the envelope holder into either their open or closed position, depending upon the direction of movement of the actuating rod. The hydraulic cylinder 65 is connected at its opposite ends to a supply of oil under pressure by means of rigid oil lines or conduits 67, 68 which are connected, through passageways in a connector block 69 mounted on top the support housing35, to flexible oil lines 70, 71 connected to a four-way control valve 65a which is actuated by a cam 65b on the main cam shaft to thereby control the supply of oil to, and therefore the operation of, the hydraulic cylinder.

As shown in Fig. 5, the thrust bearing or coupling 63 between the actuating rod 53 and the piston rod 64 of the oil cylinder 65 comprises a two-part housing '72 fixedly secured to the end of the piston rod 64 and consisting of a cup portion 73 fastened to the piston rod 64, and a cap portion 74 suitably secured to the cup portion 73, as by screw threads for instance, and having a central aperture therein through which the actuating rod 53 extends into the interior space of the housing 72. Fixedly mounted on the facing inner sides of the cup and cap members 73 and 74 of the housing 72 are ball thrust bearings 75 and 76, respectively, which, upon reciprocation of the piston rod 64, abut against a flange 77 on a thrust collar 78 fastened to the inner end of the actuating rod 53 within the housing 73 to thereby transmit the reciprocating movement of the piston rod to the actuating rod 53 while leaving the actuating rod free to rotate along with the transfer arm 33 upon rotation of the latter to efiect the inversion of the lamps 1 during the lamp transfer operation. The flange 77 of collar 78 has a close fit between the thrust bearings 75, 76, the clearance therebetween being of the order of from .001 to .002 inch or thereabouts.

The transfer arm 33 is rotated, to effect the inversion of the lamps 1 during the interval when the transfer arm is swinging from its lamp pick-up to its lamp delivery position, by means of a vertically extending slide rod 79 extending through the hollow vertical support shaft 36 and into the support housing 35 and carrying at its upper end a vertically extending rack gear 80 which is meshed with a spur gear 81 fastened on the reduced diameter portion 82 of the transfer arm 33 within the housing 35. The rack gear 80 is vertically slidable within the housing 35 in a slide bearing 83 which is mounted within and fastened to the housing 35. At its lower end, the slide rod 79 is pivotally connected, by a ball and socket connection, to one end of a more or less horizontally extending lever 84 pivoted at its other end on a bracket 85 upstanding from the machine bed plate 5. Intermediate its ends, the lever 84 carries a roller 86 which rides in the cam groove of a face cam 87 fastened on the cam shaft 10.

Upon index of a lamp-1 to the lamp transfer station Q of the first turret 6, the jaws 50, 51 of the transfer arm lamp holder 46 are first closed by the operation of the hydraulic cylinder 65 so as to cause the said jaws to firmly grip the envelope 2 of the lamp which is at such time held in the holder 14 on the turret 6. After the lamp has been thus gripped by the transfer arm holder 46, the grip of the holder 14 on the lamp is then released by the opening of the jaws 15, 16 thereof through the operation of a horizontally extending lever 88 which is pivoted on the stationary column 38 and which engages at one end with and depresses the jaw opening lever 18 of the holder 14. The other end of the holder actuating lever 88 is connected by a vertically extending link 89 (Fig. 1) to an intermediate point of a more or less horizontally extending cam lever 90 pivoted at one end on a support bracket 91 secured to a stationary portion of the machine framework, e. g., the table portion (not shown) of the second sealing machine 4. The other end of the cam lever 90 carries a roller 92 which rides on the periphery of an edge cam 93 mounted on the cam shaft 10.

Following the release of the lamp 1 by the holder 14 at station Q, the transfer arm 33 is then swung to its delivery position, by the operation of the cam 45, lever 40 and connecting link 42, to insert the lamp in the holder 14 of the head '7' which at that time is located at the loading station B of turret 6', the said holder 14 having been supplied at one or the other of the preceding two stations Q or A with a lamp mount on the upper end of its spindle 13 for sealing into the remaining open end of the lamp envelope.

Simultaneously with the said swing movement of the transfer arm 33 from its lamp pick-up to its lamp delivery position, the transfer arm is rotated through 180 degrees, in a clockwise direction as viewed from its outer end, to invert the lamp 1 through the operation of the cam 87, lever 84, slide rod 79 and the intermeshed rack and spur gears 80, 81. At the moment the lamp 1 is thus inserted in the holder 14 of the second sealing machine 4 by the transfer arm, the turret 6 is in its period of dwell and the jaws 15, 16 of the holder 14 at station B are held in their open position, against the bias of the spring 17 which normally holds the jaws in closed position, through the operation of a jaw-opening finger 94 which is carried by a vertically extending slide rod 95 and which on downward movement engages with and depresses the jawopening lever 18 of the holder. The slide rod 95 is ver- 75 tically reciprocable in a bearing 96 mounted'on a staamora tionary portion of the machine framework and it isipiv otally: connected at its lower end to one end of a hori zontally extending lever 97 which is pivoted intermediate: its ends on a bracket'98 mounted on the machine framework. At its other end, the lever 97 carries a roller 99 which rides on the periphery of an edge cam 100 mounted on the cam shaft 10.

When the lamp 1 has been thus inserted by the transfer arm into the holder 14 at station B of the second turret 6, the jaws 15, 16 of the said holder are then closed against the envelope 2 of the lamp by the elevation and dis-engagement of the jaw-opening finger 94 from the jaw-opening lever 18 of the holder which then allows the biasing spring 17 thereof to close the holder jaws against the lamp envelope so as to grip and firmly hold it in place in the head 7'. With the lamp thus held by the holder 14 at station B, the jaws 50, 51 of the transfer arm holder 46 are then opened to release the lamp by the operation of the hydraulic cylinder 65, thereby completing the transfer and inversion of the lamp from the first sealing machine 3 to the second sealing machine 4. The transfer arm 33 is then swung and rotated back to its lamp pick-up position in readiness for the next lamp transfer operation.

Upon subsequent index of the second turret 6' and positioning of the transferred lamp 1 at one of the ensuing stations (e. g., station C), the lamp is moved downwardly in the holder 14, by suitable lamp push-down mechanism (not shown) similar to that at station D of the first sealing machine 3, into proper sealing relation with the lamp mount resting on the upper end of the spindle 13 of the head 7, with the open lower end of the lamp envelope abutting against the, glass flare portion of the lamp mount. The lamp mount is then sealed to the lamp envelope in the customary manner by the conventional gas fires located at the subsequent index stations of the turret 6, after which the lamp is elevated at station by lift-up mechanism similar to that at station P of the first turret 6, and then removed from the turret 6' at one or the other of the unloading stations P, Q and another lamp mount then placed in position on the spindle 13 of the emptied head 7' in readiness for the next sealing cycle.

The location of the transfer arm 33 in the particular manner shown between the two sealing turrets 6 and 6 so as'to transfer the lamps 1 from a head 7 of turret 6 at a station Q located more or less midway between the position (station 0) wherein it is closest, during its index cycle, to the second sealing turret 6' and a position 90 degrees from such closest position, assures the transfer movement and inversion of the relatively long fluorescent lamps 1 through an area closely adjacent to the confines of the machine where they will not interfere with other objects thereadjacent and become broken, without requiring the two sealing turrets 6, 6 to be unduly spaced apart so as to enlarge the size and the over-all space requirements thereof.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. Apparatus for sealing lamp mounts into the opposite ends of tubular lamp envelopes comprising a pair of sideby-side indexing turrets each having a plurality of sealing heads thereon each supporting a lamp mount and a tubular glass envelope in sealing inter-relation with the lamp mount seated on the upper end of a spindle portion of said head and with the tubular envelope held vertically in a holder portion of said head with its open lower end abutting against the glass flare of the mount, drive means including means for indexing said turrets in timed relation with each other to advance the respective heads thereon through a series of successive index stations, transfer means located between said turrets and actuated by said drive means for transferring and inverting the lamps from an unloading index station of one of said turrets to a loading index station of the other of said itur-j 76-. said drive means for: vertically'reciprocating said slide 81 rets,,said-.transfer: means comprising a horizontally extending transfer arm rotatably mounted for rotation about its axis" on r a vertically, extending hollow support shaft, means1supportingsaid-vertical shaft for oscillation about its axis to-thereby swing said transfer arm in a horizontal plane'between a larnp pickup and a lamp delivery position; means: actuated by said drivemeans for oscillating said 'vertical'shaft, said transfer arm'having a spur gear mounted thereonand carrying aa lamp holder adjacent its outer end comprisingca pair oftlamp-gripping jaws pivotally mounted-on said transfer arm, means on said transfer arm connected' to 'said jaws and actuated by said drivemeans forlpiv'otingisaidjaws between an open position'and a closedlarnp-gripping position, a vertical slide metnber'exten'dingtthrough said vertical hollow shaft, said slide member being vertically reciprocable in said hollow shaft and carryinga rack gear meshedwith the spur gear on saidtransfer' arm tolrotateithe latter about its axis so asto invert'the lamp, and'means connected to said slide member: and actuatediby said drive means for vertically reciprocating said slide memb'er.

2. In-combination with a pair of manufacturing machines for electric lamps of the type having elongated tubular envelopes and comprising an indexing carrier having a plurality of heads mounted on the periphery thereof and supporting envelopes vertically, synchronousdrive means for said machines including means for indexingzsaidcarriers in timed relation with each other to advance" the respective heads thereon through a series ofsuccessive' index-stations, an inverting transfer mechanism comprisinga-horizontally extending elongated transfer arm rotatable about itslongitudinal axis, an envelope holder supported by said armand having lamp gripping jaws mounted to'pivot together about axes normal to said longitudinal axis, a pivotal mounting supporting said arm for oscillation in'arh orizontal plane between a lamp pickup-position at an index station of one carrier and a lamp delivery position at an index station of the other carrier, means actuated'by said drive means for oscillating said arm between said positions, means actuated by said drive means for closing said lamp gripping jaws about an envelope at the pickup station and for opening them at the delivery position, and means actuated by said drive means for rotating saidarm to rotate said envelope holder about said arm axis in the course of the oscillation of said transfer arm between said pickup and delivery positi'ons.

3. In combination with a pair of manufacturing machines for electric lamps of the type having elongated tubular envelopes, each of said machines comprising a carrier having a plurality of heads mounted on the pcriphery thereof'and supporting envelopes vertically, synchronous drive means'for said machines including actuatingmeans for indexing said carriers in timed relation with each other to advance the respective heads thereon through a series of successive index stations, an inverting mechanism comprising a horizontally extending transfer arm, an envelope holder attached to said arm adjacent its outer end andcomprising a pair of pivotally mounted lamp gripping jaws, a rotatably mounted vertically extending hollow support shaft supporting said transfer arm for oscillation in a horizontal plane between a lamp pickup position at an'index station of one carrier and a lamp delivery position at an index station of the other carrier, means actuated by said drive means for oscillating said arm between said positions, means on said transfer arm connected'to saidgripping jaws and actuated by said drive means for'closing said jaws upon an envelope at the pickup position and for opening said jaws at the delivery position, a spur gear fast to said horizontal arm, aslide membervertically reciprocablc through said hollow shaft and carryinga rack gear meshing with said spur gear to rotate saidhorizontal arm about its axis, and means connected tosaid slide member and actuated by member during oscillation of said transfer arm from said pickup position to said delivery position in order to invert the lamp envelope.

4. A transfer mechanism for picking up vertically extending lamps at one position and delivering them inverted to another position comprising a horizontally extending transfer arm, an envelope holder attached to said arm adjacent its outer end and comprising a pair of pivotally mounted lamp gripping jaws, a rotatably mounted vertically extending hollow support shaft supporting said transfer arm for oscillation in a horizontal plane between a lamp pick-up position and a lamp delivery position, means for oscillating said vertically extending hollow support shaft to oscillate said arm between said positions, means on said transfer arm connected to said gripping jaws for closing said jaws upon an envelope at the pick-up position and for opening said jaws at the delivery position, a slide member vertically reciprocable through said vertically extending hollow support shaft, means interconnecting said slide member and said horizontal arm to translate vertical reciprocation of the former into rotation of the latter about its axis, and means connected to said slide member for vertically reciprocating it during oscillation of said transfer arm from said pick-up position to said delivery position in order to invert the lamp envelope.

5. A transfer mechanism for picking up vertically extending lamps at one position and delivering them inverted to another position comprising a horizontally extending transfer arm, an envelope holder attached to said arm adjacent its outer end and comprising a pair of pivotally mounted lamp gripping jaws, a rotatably mounted vertically extending hollow support shaft supporting said transfer arm for oscillation in a horizontal plane between a lamp pick-up position and a lamp delivery position, means for oscillating said vertically extending hollow support shaft to oscillate said armbetween said positions, an actuating rod extending through the transfer arm and linked to said gripping jaws for actuation thereof, means on said transfer arm connected to said actuating rod to close said jaws upon an envelope at the pick-up position and for opening said jaws at the delivery position, a spur gear fast to said horizontal arm, a slide member vertically reciprocable through said vertically extending hollow support shaft and carrying a rack gear meshing with said spur gear to rotate said horizontal arm about its axis, and means for vertically reciprocating said slide member during oscillation of said transfer arm from said pick-up position to said delivery position in order to invert the lamp envelope.

References Cited in the file of this patent UNITED STATES PATENTS 

